The prophylactic effect of galcanezumab and erenumab on chronic migraine may be maintained 3 months after treatment termination, according to a small study published in The Journal of Headache and Pain.
In this study, the data of participants who completed the open-label extension phase of studies in which the effect of erenumab (Clinicaltrials.gov identifier: NCT02174861; 12 months) and galcanezumab (Clinicaltrials.gov identifier: NCT02614261; 9 months) on chronic migraine prophylaxis were examined in a single German headache center. Migraine data at 12 weeks after treatment termination were compared with data from the final 4 weeks of the open-label phase of the studies, considered as baseline of the double-blind phase of the trial (galcanezumab, n=9; erenumab, n=7). End points included changes in the use of acute headache medications, headache hours, monthly migraine days, and days with severe headache.
The mean number of monthly migraine days at baseline was 18.38±3.74, compared with 12.19±4.53 days in the last 4 weeks of the open-label extension (P <.001). Throughout the entire 12-week observation period after open-label termination, the number of monthly migraine days remained significantly reduced compared with baseline level (P =.002), with a reduction of 5.38±4.92 days during the week 1 to 4 period (P =.001), a reduction of 4.75±4.15 days during the week 5 to 8 period (P =.001), and a reduction of 3.93±5.45 days during the week 9 to 12 period (P =.014). No significant difference was seen in monthly migraine days between the 12-week post-open-label termination and the final 4 weeks of the open-label phase (P =.228).
Ten of the 16 participants had fewer migraine days compared with baseline at all time points, 4 patients reported ≤15 monthly migraine days during the observation period, and 2 patients had an increase of ≥2 migraine days during weeks 9 to 12 compared with baseline. Headache hours, days of severe pain intensity, days of acute headache medication use, and days of triptan use showed an increasing trend after trial termination but remained numerically lower compared with baseline at all time points. Compared with the final 4 weeks of the open-label phase, significant increases were reported in severe headache intensity during the week 9 to 12 post-termination period (P =.039), and days with triptan use increased during the week 5 to 8 post-termination period (P =.032).
“[These results] suggest continuous efficacy of [monoclonal antibodies] against [calcitonin gene-related peptide] (CGRP)/CGRP receptor in the prevention of chronic migraine up to 12 weeks after treatment discontinuation. Monitoring the headache pattern by headache calendars is an essential tool to determine the most suitable long-term therapy strategy for each patient,” noted the study authors
Study authors have received honoraria for consulting and presentations from and/or are involved as clinical trial investigators without personal remuneration for Amgen, Alder, Autonomic Technologies, Co-Lucid, Desitin, Eli Lilly, Hormosan, Medscape, Novartis, Pharm Allergan, StreaMedUp, and TEVA.
Raffaelli B, Mussetto V, Israel H, Neeb L, Reuter U. Erenumab and galcanezumab in chronic migraine prevention: effects after treatment termination. J Headache Pain. 2019 Jun 3;20(1):66.